Ice maker heater circuit



Nov. 22, 1966 T. B. cHAcE ET AL ICE MAKER HEATER CIRCUIT 5 Sheets-Sheet 1 Filed May 17, 1965 0L ENO/0 VL VE jaa 65 I NVENTORS 7 @m515 @we 0'56 @0H-TT ORNE YS Nov. 22, 1966 T. B. cHAcE ETAL ICE MAKER HEATER CIRCUIT 5 Sheets-Sheet 2 Filed May 17, 1965 I N VE N T0125 2 kami?. CZzafce Nov. 22, 1966 T. B. CHACE ET AL 3,286,478

ICE MAKER HEATER CIRCUIT Filed May 17, 1965 5 Sheets-Sheet Z5 INVEN TOR.

NOV. 22, 1966 T, B, CHACE ET AL 3,286,478

ICE MAKER HEATER CIRCUIT Filed May 17, 1965 5 Sheets-Sheet 4 f 15H7 W I v/55 kw? figg/7 45 y Z2 BY and MTORNEYS Nov. 22, 1966 T. B. cHAcE ET AL 3,286,478

ICE MAKER HEATER CIRCUIT Filed May 17, 1965 5 Sheets-Sheet .5

INVENTOR @hace `@figg/220 BY 4M www 7?@11@ f90 *WOM/HYS United States Patent O 3,286,478 ICE MAKER HEATER CIRCUIT Thomas B. Chace, Winnetka, and Joseph M. Algino, Chicago, Ill., assignors to The Dole Valve Company, Morton Grove, Ill., a corporation of Illinois Filed May 17, 1965, Ser. No. 456,125 Claims. (Cl. 62.-135) This invention relates generally to ice making apparatus and more particularly to an automatic ice cube maker wherein the ice cubes are formed in trays or the like and then ejected therefrom for use or for collection in a collection basket and wherein the forming and ejecting operations are performed in successive cycles of operation which require given time periods of duration.

More specifically the present invention is directed to a method 4and apparatus for controlling the time cycle of a forming and an ejecting operation whereby the cubes are sufficiently hardened in the forming means prior to ejection thereof to preclude premature ejection before the cubes are sufficiently formed and hardened.

The ice cube maker of this invention utilizes a temperature responsive power element to power the ejector mechanism. A heat source is associated with the power element to actuate same. As heat is applied to the power element a force applying member thereof which is operatively connected to the ejector mechanism moves from a first position to a second position, and upon the discontinuance of the Aapplication of heat and the cooling of the power element the force applying member moves from the second position thereof back to the first position,

It is this movement of the force applying member lfrom a first position to a second position and back to the first position which actuates the ejector mechanism through an ejection operation. The length of time required for this movement determines the time cycle of a complete forming and ejection operation.

Since successive forming-ejection operations or cycles follow consecutively the time period in which a cycle takes place and consequently the time period during which the force applying member moves from its first position to its second position and back to its first position becomes important in order to preclude premature ejection or dumping of the cubes before they have fully formed and hardened.

An object of the present invention is to provide a method and apparatus for controlling the time interval of a complete ice forming-ejection cycle.

Another object is to extend the cooling down period of the temperature responsive power element whereby the length of time required for the force supplying member to move back from its second position to its first position is increased, thereby increasing the time interval of an ice forming-ejection cycle.

Another object of the invention is to control the heat applied to the temperature responsive power element such that it is subjected to a high capacity heat source for movement of the force supplying member from its first to its second position and is then subjected to a low capacity heat source whereby the power element cools down slowly and the length of time required for the force supplying member to move back to its rst position is increased.

A further object of the Iinvention is to provide electric heating means and suitable circuitry therefor for actuating the temperature responsive power element and including means for extending the cooling down period of the element subsequent to the heating thereof.

Still another object of the invention is to provide electric circuitry for controlling the heat applied to the tem- 3,286,478 Patented Nov. 22, i966 perature responsive power element including switch means for energizing the circuitry in response to the positioning of the force applying member, and including means for `delaying movement lof this member to delay actuation of the switch means.

Another object of the invention is to provide electric circuitry including an electric heater element for heating the power element to a predetermined temperature and including means which may comprise a resistor, a separate heater element, or the like, connected in the circuitry to extend the time period during which the power element cools down after such predetermined temperature has been reached.

Many other features, advantages and additional objects of the present invention will become manifest to those versed in the art upon making reference to the detailed description which follows and the accompanying sheets of drawings, in which perferred structural embodiments incorporating the principles of the present invention are shown by wayV of illustrative example only.

In the drawings:

FIGURE l is a front elevational view of exemplary ice making apparatus constructed in accordance with the principles of the present invention and mounted for purposes of illustration in the freezer compartment of a household refrigerator;

FIGURE 2 is a vertical sectional view taken substantially along lines II-II of FIGURE 1 with the .ice trays of the apparatus removed for clarity and with mounting brackets for the ice trays shown in upright positions in full lines and with one of the mounting brackets shown in a tilted position in broken lines;

FIGURE 3 is similar to FIGURE 2 but illustrates in broken lines the other of the mounting brackets in a tilted or inverted position;

FIGURE 4 is a side elevational view of the ice making apparatus of FIGURE 1 as viewed from the left-hand side thereof;

FIGURE 5 is an enlarged fragmentary perspective view of a clutch and a switch mechanism of the ice making apparatus of FIGURE 4;

FIGURE 6 is a schematic diagram of electric circuitry which may be employed in controlling the operation of the ice making apparatus;

FIGURES 7-10 are schematic w-iring diagrams similar to that shown in FIGURE 6 but including improvements constructed and arranged according to the present invention;

FIGURE ll shows a portion of the side elevational view of FIGURE 4 with parts removed to emphasize the clutch mechanism of the invention;

FIGURE l2 is sim-ilar to FIGURE 5 but shows the clutch and switch mechanism in an operating position different from that shown in FIGURE 5; and

FIGURE 13 is a similar to the schematic wiring diagram of FIGURE 6 but includes a water fill valve for supplying water to the ice trays.

As shown in the drawings:

The principles of the invention are applicable to lany automatic ice maker apparatus which incorporates an ejector mechanism actuated by a temperature responsive power element and the illustrated embodiment of one ysuch apparatus shown in the accompanying drawings is merely exemplary of a wide variety of ice makers which may employ a temperature responsive power element.

The illustrated embodiment comprises automatic ice making apparatus suitable for making ice cubes in a household refrigerator and in FIGURE 1 is indicated generally at reference character 10 mounted in a freezer compartment 11 of a household refrigerator 12.

Referring to FIGURES 2-4 in conjunction with FIG- URE 1, the apparatus is more particularly characterized as comprising a three-sided or U-shaped frame 13 and a rectangularly shaped box or casing 16 fixedly connected to the frame 13 at the open end thereof. The casing 14 houses the operating or driving mechanism of the ice making apparatus 10.

A pair of ice cube trays 17 and 18 are situated in spaced parallel relation within the confines of the frame 13. Each of the trays is supported at opposite ends thereof for rotation about its longitudinal axis by means of a pair of ytray mounting brackets. For example, the tray 17 is fixedly connected at one end thereof to a tray mounting bracket 19a which is mounted for rotation on a small shaft or pin 20a which projects from an end plate 16 of the frame 13. An opposite end of the tray 17 is carried on a similar tray mounting bracket which is mounted for corotation on a rotatable shaft 21a which is in turn journalled on a back wall 14a of the casing 14.

The tray 18 is sim-ilarly mounted for rotation about its longitudinal axis on a mounting bracket 19b carried on a pin 20b and on another bracket at the opposite end thereof carried on a shaft 2lb which is in turn journalled on the wall 14a. It will be noted that the forward or front tray 18 is mounted slightly higher than is the rear tray 17.

An ice collection basket 22 is shown positioned below the trays 17 and 18 in order to receive and collect the ice cubes ejected from the trays and in the illustrated embodiment the basket 22 rests on a bot-tom wall 23 of the freezer compartment 11.

The present invention actually contemplates completely automatic formation of ice or ice particles such as cubes in an operation or cycle that may consist of, for example, the steps of first automatically filling one of the trays with water to a predetermined level, than rotating the other of the trays to dump or eject ice cubes previously formed therein into the ice collection basket, then filling said other of the trays with water for the formation of additional cubes, then rotating said one of the trays to dump the ice cubes then formed therein, and then repeating the operation or cycle over and over until the amount of ice in the collection basket, as determined by an automatic collection sensing arrangement after each tray is dumped, is sufficient so that additional cubes are not required. The operation then ceases until such time as enough cubes have been removed from the collection basket so that the sensing arrangement is effected to cause a resumption of the ice forming operation.

The mechanism for automatically and successively filling the trays with water comprises a nozzle 24 (FIGURE 1) positioned above the trays 17 and 18 and connected by means of suitable plumbing circuitry to a source of water. A water valve indicated at 26 is incorporated in the plumbing circuitry to supply a predetermined amount of water to the trays for the ice form-ing operation.

The water which flows from the nozzle 24 is directed to a stationary trough 27. A lower end 28 of the trough 27 comprises an open lip 29 from which the water flows to a forwardly downwardly inclined surface 30 of a swingable trough 31, which is positioned as illustrated in FIGURE 3 to fill the forward or front ice tray 18, or to a backwardly downwardly inclined surface 32, positioned as shown in FIGURE 2, to fill the rear trays 17.

The swingable trough 31 is mounted on an arm 33 which is, in turn, pivotally mounted on the shaft 20b. The arm 33 is pivoted between the positions illustrated in FIGURES 2 and 3 by meansof a sliding arm 34 guided for reciprocal rectilinear movement by means of a pair of U-shaped guide members 36 and 37 mounted on the wall 16 of the frame 13 and having extending from a protrusion 38 thereof a pin 39 which is received in a slot 40 formed in the pivot arm 33.

Suitable abutment surfaces 41 and 42 are formed respectively on the tray mounting brackets 19a and 19b to engage opposite end surfaces 43 and 44 of the slidable arm 34 so as to move the arm back and forth as the mounting brackets are turned or inverted.

The ice trays 17 and 18 may be of the type which dislocate and dump ice cubes formed in the ice wells thereof when the trays are turned and somewhat twisted about their longitudinal axis. Such trays are known, and may be formed of a plastic, flexible material suchas high density or linear polyethylene or the like composition although it will be appreciated from the ensuing description of the invention that other trays and other ice forming mechanisms having different modes of dislocating ice particles therefrom can also be advantageously utilized.

As noted, much of the operating mechanism of the apparatus 10 resides within the box or casing 14, and referring to FIGURE 4, wherein the greater portion of an end wall 141i of the casing 14, situated opposite the end wall 14a, is cut-away for purposes of clarity, it will be noted that a pair of sector gears 46a and 46b are fixedly mounted on the shafts 21a and 2lb for corotation with the shafts. The shafts 21a and 2lb are, as noted, journalled for rotation on the end wall 14a of the casing 14.

Sector gears 46a and 46b are formed with gear teeth 47a and 47b thereon which extend, respectively, in an arc of about and in the positions of the sector gears shown in FIGURE 4, wherein teeth 47a are facing substantially upwardly and the teeth 47b are facing substantially downwardly, the shafts 21a and 2lb are positioned such that the tray mounting brackets 19a and 19b are in their normal or upright positions as shown in the full lines of both FIGURES 2 and 3.

In accordance with the invention suitable power means are provided for alternatively rotating the sector gears 46a and 46b through the arc of the gear teeth formed thereon, and correspondingly for rotating their respective shafts 21a and 2lb, in order to tilt or invert the ice trays 17 and '18, and in the illustrated embodiment such power means comprises a temperature sensitve or temperature responsive power unit indicated generally at 48 having a telescopically extensible piston or force applying 'member 49 which projects outwardly from a retracted or first position thereof as shown in FIGURE 4 to an extended or a second position upon the application of heat to the power unit 48.

The power unit 48 is fixedly connected to the wall 14a of the casing 14 along with a fiat elongated guide member 50 which extends in parallel relation to the axis of the power unit 48 and which has an axially extending track means or groove 51 formed therein for guiding in rectilinear movement a sliding bracket 52.

An axially adjustable threaded plug 53 is mounted on the sliding bracket 52 in coaxial alignment with the piston or plunger 49 for adjusting the relative spaced relationship of the bracket 52 with respect to the piston 49.

Biasing means are provided for biasing the sliding bracket 52 toward the power unit 48 so that an end wall 54 of the plug 53 is maintained in abutting engagement with an end wall 56 of the plunger 49 and for this purpose a coil spring 57 having a relatively high k factor is bottomed at one end thereof as at 58 against a shoulder 59 of the bracket 52, and is bottomed at an opposite end thereof as at 60 against a fiange 61 mounted in fixed assembly on the casing wall14a.

.The temperature responsive power unit 48 is of a type well known in the art and includes a temperature sensitive portion 62, a collar 63 and a guide portion 64 in addition to the telescopically extensible plunger or force applying member 49.

Suitable lheating means which, in the illustrated embodiment of the invention, comprises a heater coil 66, is wrapped around the temperature sensitive portions 62 and it will be appreciated that when the coil 66 is electrically energized or otherwise actuated to produce heat, the

force applying member or plunger 49 will move gradually outwardly from its first or retracted position as illustrated in FIGURE 4 to a second or extended position. The sliding or follower bracket 52 follows the movement of the plunger 49, and upon deactivation of the coil 66 and the cooling down of the temperature sensitive portion 62, the plunger 49 will gradually retract to its retracted position as shown in FIGURE 4 due to the biasing effect of the spring 57.

As illustrated in FIGURE l1, a sloping gear rack 70 is formed on a lower portion 71 of the follower or sliding bracket 52 and is adapted to mesh with gear teeth 72 formed lon a complementarily shaped spiral-form drive gear 73 mounted for free rotation on a shaft 74 supported between the walls 14a and 14b of the casing 14.

The drive gear 73 has formed therein a radially outwardly extending groove or channel 76 which receives in sliding relation a pawl member 77 which is biased radially outwardly of the channel 76 by means of a helical spring 78.

It will be apparent that as the plunger or force applying member 49 moves from its retracted position as shown in FIGURE 4 to an extended position upon actuation of the heater 66, the drive gear 73, and correspondingly the pawl 77, is rotated from the position thereof shown in FIGURE 4 to the position thereof shown in FIGURE ll, whereby the pawl 77 has rotated approximately 90.

Also mounted for free relative rotation on the shaft 74 axially of the drive gear 73 is a multi-faced gear 79 having an axially extending recess 80 formed therein which is bounded at the periphery thereof by a circumferentially continuous axially extending peripheral wall 81. The axial depth of the recess 8i) is sufficient such that a substantial portion of the drive gear 73, but excluding, of course, the gear teeth 72, is housed within the recess 80;

Along an outer peripheral wall 82 of the gear 79 are various sets of gear teeth for engaging and for driving the sector gears 21a and 2lb. As best shown in FIG- URES 5 and 12, some of the gear teeth as at 83 are formed adjacent one axial end 84 of the outer peripheral wall 82, and in the same arc in which the teeth 83 are formed the opposite side of the wall 82 adjacent an axial end 86 th-ereof is void of gear teeth.

Another set of gear teeth 87 is formed on the outer peripheral wall 82 and extends circumferentially in an arc adjacent the arc in which the gear teeth 83 residues, and it will be noted in connect-ion with teeth 87 that the side of the wall 82 adjacent the axial end l84 thereof is blank, while the teeth S7 are in this instance formed 'along the axial end 86 of the wall 82.

The sector gears 46a and 46b are normally maintained in the positions shown in FIGURE 4 by means of suitable biasing members which, in the illust-rated embodiment, comprise respectively a ltorsion spring 88 wound about the shaft 21aand connected at opposite ends thereof to the shaft .and to the sector gear 46a, 'and a tension spring I89 connected at one end thereof to the sector gear 4617 and at an opposite end thereof to the casing wall 14a.

In addition, the body portions of the sector gears 46a and 46b are offset with respect to the planes in which the gear Iteeth 47a land 47h reside, such that the gear teeth 47a of the sector -gear 46a will mesh with the gear teeth r83 of the multi-face gear 79, but will not mesh with gear teeth 87, and the teeth `47h of the sector gear 46h will mesh with teeth 87 of the gear 79, but not with teeth 83.

Referring again to FIGURE ll, the peripheral wall 81 of the multi-face gea-r 79 comprises a plurality of circumferential segmental per-tions with each of said portions comprising `a circular span or section 99 which leads to a radially inwardly inclined section 91 which terminates at a lradially extending shoulder surface 92.

Referring to FIGURE 5, it will be noted that each of the shoulder surfaces 92 also forms an end wall of a 6 recess 95 -formed in the axial end wall 84 of the gear 79, each of said recesses `also being bounded by another wall 93 spaced circumferentially with respect to wall 92, and a radially extending back wall 94.

The drive gear 73 and the pawl 77 comprise a clutch mechanism for translating reciprocal rectilinear movement of the follower bracket 52 into intermittent r-otational movement of the multi-faced gear 79, -an-d for this reason it will be noted that the pawl 77 comprises a pillar or abutment column 96 against which one end of the spring 78 bottoms. A radially outwardly facing wall 97 of the pawl is positioned to slidingly engage the inner peripheral wall v81 of the gear 79, and to be -guided in radial movement thereby. Another wall of the pawl, namely, a radially extending side wall 98, is shaped complementarily to the shoulder surfaces 92.

Referring to FIGURE 4, the heater 66 may comprise an electric coil, and when the coil is deenergized and the power unit 48 has cooled and the plunger 49 has moved to its retracted position, the follower bracket 52 is situ-ated in its rightward position as illustrated in FIGURE 4, and the radi-al wall 98 of the pawl 77 is in abutting engagement with one of the shoulder surfaces 92 of the multifaced gear 79.

Subsequently, upon energization of the coil 66, as the plunger 49 moves :outwardly to its secon-d or extended position, the follower bracket 52 is moved leftwardly, whereupon the drive gear 73 is rotated approximately 90 in a :counterclockwise direction. As la result `of this rotation -of the drive vgear '73, the gear 79 is `also rotated through the same arc by the pawl 77.

As the gea-r 79 is rotated counterclockwise the gear teeth 87 lformed .thereon will engage yand mesh with the gear teeth 471) of the sector .gear 46b and rotate the gear 46b clockwise for labout 90 or more degrees to tilt or twist the ice .tray 18, whereupon the ice will be dumped from the tray. The teeth -87 a-re arranged so as to extend in an ar-c which is less than the arc through which the gear 79 rotates as a result of the rotation of the drive gear 73. As a consequence, after all of the teeth 47b have meshed with corresponding Iteeth 87 of the gea-r 79 they are then exposed to a blank portion of the gear 79, upon the happening of which the sec-tor -gear 46b will immediately spring back to its normal position as viewed in FIGURE 4, thereupon returning `the ice tray 18 to its norm-al or upright position.

As the power unit 48 cools upon de-energization orf the coil 66, land the plunger or force applying member 49 is retracted, the follower bracket S2 moves rightwardly whereupon the drive gea-r 7 3 is rotated clockwise. -During such clockwise rotation the pawl 77, the radial wall 97 of which is urged against the inner peripheral wall 81 of the -gear 79 by the spring 7S, is guided first by the circular section 90 of the wall S1, and then by the radially inwardly inclined section 91 thereof until the Iradial wall 98 of the pawl is moved back again to snap into abutment with another shoulder surface 92 as shown in FIGURE 4. -It will be appreciated that during this clockwise rotation of the driver gear 73 the multi-faced gear 79 lremains stationary. The next time the coil 66 is energized, and the drive gear 73 is against rotated approximately 90 countercl-ockwise, the gear teeth 83 of the gear 79 will engage the teeth 47a of the sector gear 46a to tilt or twist the ice tray 17, the sector gear 46h and the ice tray 18 being maintained in normal or upright position during this phase of the operation. It will be appreciated, therefore, that each time Ithe coil 66 is enerlgized and the plun-ger 49 moves to its extended position, and then the coil is `de-energized and the plunger retracted, the multi-faced -gear 79 :has been rotated approximately 90 in a c-ounterclockwise direction and one of the ice trays has been tilted and dumped.

Referring to the schematic wiring diagram of FIG- URE 13, the electric heating coil 66 may be connected through suitable electric circuitry including a safety switch 105 to a pair of conta-cts 99 and 100 for connection to a source of electric power, Iand Isuch electric circuitry may comprise an electric switch indicated gene-rally at 101 having a pair of electric contacts :102 and 103 which are normally biased in spacedeapart relation by means of an electrically conductive spring 104.

The water valve 26 (FIGURE \1) may be elect-rically operated vfor supplying water in predetermined quantities to the ice trays 17 and |18 and may comprise 4an electric solenoid valve indicated generally at 106 and having solenoid operating member 107 and an electric coil or winding 108 connected in parallel with the electric heati-ng c-oil 66.

In addition, the water valve 26 comprises a valve housing 109 having a chamber 110 `formed therein and adapted to receive a slidable member or piston 111 which is biased in one direction by a spring member 112.

The valve housing 109 is connected by means of a t'hroat 113 to a conduit 114 having formed therein a pair of valve seats 116 and 117.

A valve rod 118 projects at one end thereof into the coil 108 and at the other end thereof into the conduit 114, and has mounted thereon a pair of valve members 119 and 120' which .are spaced a distance less than the distance between the valve seats 116 and 117. A tension spring 121 is wrapped about the rod 118 centrally thereof and is bottomed at one end thereof as at 122 against a stationary member 123, while an opposite end 124 thereof is bottomed against a spring collar 126 connected in fixed assembly to the rod 118 whereby the valve member 119 is normally biased against the valve seat 116.

One end of the conduit 114, as at reference numeral 127, is adapted to be connected to Va source of water, while the opposite end of the conduit 114 lforms the water nozzle 24 (FIGURE 1) which overlies the stationary trough 27.

It will thus be apperciated that when the heating coil 66 is energized, the water valve solenoid coil 108 will also 'be energized to urge the rod 118 rightwardly as viewed in FIGURE 13, thereby seating the valve member 120 against the valve `seat 117. Supply water then flows to the conduit 114 Xand the throat 113 into the chamber 110 to urge the piston member 111 downwardly in response to the pressure of the Water source.

When the solenoid coil 108 is de-energized, the spring 121 urges the rod 118 leftwardly as viewed in FIGURE 13, to again seat the valve member 119 Iof the valve seat 116, whereupon the piston member 111 for-ces the water contained in the chamber 110 out through the nozzle 28 to fill one of the ice trays.

Electric switch 101 is actuated by the pawl 77 of the clutch mechanism, 'and refe-rring again to FIGURE 5, it will ibe noted that the electrically conductive spring 104 which has the contact 103 formed thereon is positioned adjacent the axial end wall 84 of the gear 79. In addition it will be noted that the spring 104 also has mounted thereon a radial wall 128 and an inclined wall 1.29. A toip wall 130 of the pawl 77 terminates in a front portion 131 which also slopes similarly to the inclined wall 129. The top wall 130 of the pawl 77 extends circumferentially a distance greater than the circumferential distance between the shoulder surface 92 and the wall 93 of the multi-faced `gear 79, so as to effectively span the gaps formed by the respective recesses 95 and the end wall 84 of the gear 79.

The switch 101 and the conductive spring 104 are fixedly mounted on the wall 14b of the casing 14, and the radial wall 128 of the spring 104 is situated so as to move downwardly adjacent a shoulder surface 92 into a recess 95 due to the inherent lbias of the spring 104. As a consequence the electric contact 103 formed on the spring 104 is normally in spaced-apart relation with respect to the stationary contact 102 as a result of the bias ofthe spring 104.

It vwill be noted, however, that as the driver [gear 73 and the pawl 77 are rotated clockwise with respect to the gear 79, and particularly when the pawl 77 passes a shoulder surface 92 thereby to be moved radially outwardly due to the spring 78 (such action of the pawl 77 occurring upon complete retraction of the plunger 49) the sloping wall 131 of the pawl 77 engages the inclined -wall 129 of the spring 104 to move the contact 103 into abutting engagement with contact 102, thereby energizing both the heating coil 66 and the solenoid 108 of the water valve 26.

After the heating coil 66 is energized, the driver gear 73 along with the pawl 77 and multifaced gear 79 will begin to move corotatably counterclockwise. The electric contacts 102 and 103 will remain closed, however, since the radial wall 128 of the switch spring 104 will remain in engagement with the top Wall 130 of the pawl 77 until the pawl rotates past the radial wall 128, whereupon the wall 128 will engage the axial end wall 84 of the gear 79 to prevent movement of the spring 104 and to maintain the contacts 102 and 103 in closed relation.

After the driver gear 73 and the multi-faced gear 79 have rotated about another shoulder surface 92, and a recess formed in the end wall 84 adjacent thereto, will move into Ialignment with the radial wall 128 of the spring 104, whereupon the radial wall 128 will be urged down into the recess thereby opening the electric contacts 102 and 103 to de-energize the electric Iheating coil 66.

As the temperature responsive power unit 48 is cooled and the plunger 49 thereof retracted, the driver gear 73 as well as the lpawl 77 will again rotate clockwise, and ias the wall 98 of the pawl passes thel shoulder surface 92 which hm moved into position adjacent the radial wall 128 of the spring 104, the pawl will then be urged radially outwardly, thereupon engaging the spring 104 to once again close the electric contacts 102 and 103 to energize the electric heating coil 66.

It will thus be appreciated that the ice forming cycle whereupon each of the ice trays 17 and 18 is successively and alternatively lled with water and then twisted and inverted to dump the ice therefrom is a continually operating process. yIt should be noted, however', that the length of time required to retract the plunger 49 should be sufficient to enable the water in the ice trays to freeze before the respective trays are inverted and dumped upon subsequent heating of the power unit 48.

A simplified drawing of the schematic wiring diagram of FIGURE 13 is shown in FIGURE 6, wherein certain parts are removed -for the sake of clarity, and wherein parts similar to those shown in FIGURE 13 are given like reference characters.

In order to prevent an excess accumulation of ice cubes in the collection basket 26 means are provided for sensing such excess accumulation and for discontinuing the ice forming operation until a sufficient quantity of cubes have been removed from the basket.

Referring to FIGURES l, 4 and 5, an elongated rod or sensing arm 132 is pivotally mounted on the casing wall 14a for movement across the top of the collection basket 22. A yoke member 133 is pivotally mounted on the shaft 21a and pivotally connected by lmeans of la pin 134 to a cam member 136 carried on the shaft 74.

The cam member 136 and the yoke member 133 are rocked back and forth by means of the pillar 96 of the pawl 77 and a spring 137 in response to counterclockwise and then clockwise rotation of the pawl as the power unit 48 first expands and then retracts. A ange 138 is formed on the cam 136 in such a manner so as to restrict movement of the pawl in the event that the yoke member 133 is restricted in its rocking movement as a result of a restriction to the traversing movement of the sensing arm 132 above the collection 'basket because of an eX- cess accumulation of ice.

Since the principles of the present invention do not involve the ice sensing arrangement a more detailed description thereof is not deemed necessary.

As noted with respect to the ice forming and ejection operations, the length of time required for the plunger or force applying member 49 to retract from its extended position after the heater 66 is deenergized should be sufficient to enable the water in the respective ice trays to freeze before they are twisted and dumped upon subsequent energization of the heater 66.

Assuming that the "k factor of the spring 57 is constant, an important factor in determining the length of time during which the plunger 419 withdraws to its retracted position is the temperature of the air surrounding the power unit 48.

For example, referring to FIGURE 1 it will be noted that the casing 14 which houses the power unit 48 is situated within the freezer compartment 13 and as a result the temperature of the air surrounding the power unit 48 in this embodiment is generally quite low.

As a consequence the plunger 49 may be retracted prematurely and another cycle commenced before the water in the trays 17 and 18 are sufficiently formed and hardened.

In accordance with the principles of the present invention means are provided for controlling the cooling down period of the power unit 48 and thereby controlling the time cycle of a ice forming and ejection operation.

For example, referring to the wiring diagram of FIG- URE 7, wherein parts similar to those shown in FIGURE 6 are given like reference characters, a resistor 140 is indicated as being wired in parellel with the switch 101 and in series with the heater 66 which is wrapped around the power -unit 48. As a result, when the switch 101 is moved to an open position (FIGURE 12) as a consequence of the movement of the plunger 49 from its retracted to its extended position a `small amount of current continues to flow through the heater 66y to increase the cooling down period of the power unit 48.

As the result of the high resistance of the resistor 140l the current which fiows through the heater 66 in the open position of the switch 101 is not sufficient to prevent the plunger 49 from returning completely to its retracted position but is only of sufficient magnitude to extend the period of time required for the plunger to move to its retracted position. In addition the fiow rate of current through the coil 108 of the solenoid 106 in the open position of switch 101 is much less than that required to operate the water valve.

The resistor 140 may be of the adjustable type such that the resistance thereof can 'be adjusted according to the temperature of the ambient air surrounding the power unit 48, and if desirable the resistor itself can be situated with respect to the power unit such that the heat given off thereby can also be utilized to warm the ambient air around the power unit or to actually radiate heat generated thereby to the power unit in orde-r to supplement the heat generated by the heater 66.

According to the principles of the invention other arrangement can 'be utilized for providing a reduced amount of heat to the power unit 48 to extend its cooling down period. For example, referring to FIGURE 8 the resistor 140 is indicated as being wired in series with a thermostatic element 141 which controls the operation of a compressor motor used in the refrigeration cycle of the refrigerator 12. The thermostat 141 may 'be positioned within the freezer compartment 11 to detect a rise in temperature in the freezer compartment attendant with the lling of an ice tray with water. As the result of this arrangement the thermostat serves not only to energize the compressor motor as the result of this rise in temperature but also serves to energize the resistor 140.

Another arrangement of the invention is shown in FIGURE 9 and includes a thermostat 142 having a thermostatic element 143 connected in series with the compressor motor and also having an on-off switch 144 connected in series with the resistor 140 for providing `supplemental heat to the power unit 48 whenever the on-off switch 144 is set within a predetermined temperature range.

The switch 144 may comprise, for example, an elongated conductive bar 146 having opposite end portions 147 and 148 and a movable conductive blade 149 rotatable about an axis 150 of the thermostat 142 and operative to control the 4setting of the thermostatic element 143. As the blade 149 is rotated counterclockwise from its position as shown in solid lines to the position shown in dashed lines at 151 it makes engagement with the bar 146 to energize the resistor 140. In all positions of the blade 149 between the end portions 147 and 148 of the bar 146 electric contact is established between the blade and the ba-r and as a consequence the resistor 140 and the heater 66 are energized throughout this corresponding range of the setting of the thermostat 142.

In another embodiment of the invention shown in FIGURE 10 an auxiliary heating element 152 is connected in parallel with the heater element 66 on a side of the switch 101 opposite that of the heater 66. The auxiliary heater 152 may also be wound about the power unit 48 or may be proximately spaced therefrom depending upon the heating capacity thereof, the temperature of the ambient air surrounding the power units 48 and other such pertinent factors.

In addition the auxiliary heater 152 may :be wired in series with a thermostat 141 whereby the energization of the auxiliary heater is controlled by the operation of the thermostat.

Thus there has been provided means for controlling the cooling down period of the power unit 48 and thereby controlling the overall time cycle of a complete ice forming and ejection operation so as to preclude premature turning and dumping of the ice trays before the water therein has completely formed and solidified. As noted the principles of the invention are applicable to any automatic ice cube apparatus which utilize-s a temperature :responsive power unit to operate the ejection mechanism.

Although minor modications might be suggested by those versed in the art, it should be understood that we wish to embody within the scope of the patent warranted hereon all such modifications as reasonably come within the scope of our contribution to the art.

We claim as our invention:

1. In an ice maker,

means for forming ice cubes,

ejection means associated with said forming means and operative through successive cycles ingiven time periods to eject ice cubes from said forming means seriatim,

power means including a temperature responsive power element having a force applying member operatively connected to said ejection means,

said force applying member being moved from a first position to a second position upon the raising of the temperature of said power element to a high temperature and being moved back again to said first position upon the cooling down of said power element to a lower temperature to power said ejection means through an operating cycle,

first heating means functionally connected to said power element and operative intermittently whereupon the temperature of said power element is first raised to said high temperature and is then cooled down to said second temperature, and

second heating means also functionally connected to said power element and operative when said first heating means is inoperative to delay the cooling down of said power element and to increase the time period during which said ejection means operates through a cycle.

1 1 2. In an ice maker, means for forming ice cubes, ejection means associated with said forming means and operative through successive cycles in successive time periods to eject ice cubes from said forming means, temperature responsive power means operatively connected to said ejection means for powering said ejection means through an operating cycle when said power means is raised to a high temperature and then cooled again to a low temperature, and electric circuit means connectable to a source of electric power and comprising an electric heater situated with respect to said power means to provide a source of heat therefore, and means for alternatively increasing the electric power of said circuit to raise the temperature of said power means to said high temperature and then decreasing the electric power of said circuit to enable said power means to cool slowly to said low temperature. 3. In an ice maker, means for forming ice cubes, ejection means associated with said forming means and operative through successive cycles in successive time periods to eject ice cubes from said forming means, temperature responsive power means operatively connected to said ejection means for powering said ejection means through an operating cycle when said power means is first raised to a high temperature and then cooled again to a low temperature, and electric circuit means connectable to a source of electric power and comprising an electric heater situated with respect to said power means to provide a source of heat for said power means, and means for successively increasing and decreasing the ow of current through said heater means to alternatively increase the temperature of said power means to said high temperature and then to slowly decrease the temperature of said power means to said low temperature thereby extending the time periods of the ejection cycles. 4. In an ice maker, means for forming ice cubes, ejection means associated with said forming means and operative through successive cycles in successive time periods to eject ice cubes from said forming means, temperature responsive power means operatively connected to said ejection means for powering said ejection means through an operating cycle when said power means is raised to a high temperature and then cooled again to a low temperature, and electric circuit means connectable to a source of electric power and comprising an electric heater situated with respect to said power means to provide a so'urce of heat for said power means, switch means connected in series with said heater and movable between open and closed positions, and a resistor connected in series with said heater and in parallel with said switch means to maintain a small flow of current through said heater when said switch is in its open position to delay cooling of said power means and to extend the time periods of said ejection cycles. 5. In an ice maker, means for forming ice cubes, ejection means associated with said forming means and operative through successive cycles in successive time periods to eject ice cubes from said forming means, temperature responsive power means operatively connected to said ejection means for powering said ejection means through an operating cycle when said power means is raised to a high temperature and then cooled again to a low temperature, and electric circuit means connectable to a source of electric power and comprising an electric heater situated with respect to said power means to provide a source of heat therefor,

switch means in said circuit movable between open and closed positions to effectively deenergize said heater means in the open position thereof, and

a resistor connected in series with said heater and parallel with said switch means, said resistor also being situated physically with respect to said power means to provide a supplemental source of heat when said switch is open to delay cooling down of said power means and to extend the time periods of said ejection cycles.

6. The ice maker is defined in claim 5 wherein said resistor is of the adjustable type in order to vary the amount of supplemental heat being provided thereby to said power means.

7. In an ice maker,

means for forming ice cubes,

ejection means associated with said forming means and operative through successive cycles in successive time periods to eject ice cubes from said forming means, temperature responsive power means operatively connected to said ejection means for powering said ejection means through an operating cycle when said power means is first raised to a high temperature and then cooled again to a low temperature, and electric means connectable to a source of electric power and comprising an electric heater for heating said power means,

switch means in said circuit to effectively deenergize said heater means in the open position thereof, and

a resistor and a compressor thermostat both conected in series with each other and with said heater and both connected in parallel with said switch means whereby a small amount of heat is provided for said power means when said switch is open and said compressor thermostat is closed.

8. In an ice cube maker having ice forming means, an ejection mechanism for ejecting ice cubes from said forming means and a temperature responsive power element for powering said ejection mechanism, the improve- `ment of electric heating means for intermittently heating said power element comprising electric circuit means connectable to a source of electric power,

a heating element in said circuit means and situated adjacent said power element for providing heat to said power element,

switch means connected in series with said heating element for efecitvely deenergizing said heating element, and

supplemental heating means connected in lparallel with said switch means for providing a small amount of heat to said power element when said switch is in an open position.

9. In an ice cube maker having ice forming means, an ejection mechanism for ejecting ice cubes from said forming means and a temperature responsive power element for powering said ejection mechanism, the improvement of electric heating means for heating said power element comprising electric circuit means connectable to a source of electric power,

a heating element in said circuit means and situated with respect to said power element to provide heat to said power element upon energization thereof,

v13 switch means connected in series with said heating element for effectively deenergizing said heating element in an open position of said switch means, and

a resistor and a compressor thermostat both connected in series with each other and with said heating element and both connected in parallel with said switch means,

said thermostat being operative to energize said resistor to cause a small amount of current to ow through said heating element when said thermostat is set within a given temperature frange regardless of the position of said switch means.

10. In an ice cube maker having ice forming means, an ejection mechanism for ejecting ice cubes from said forming means and a temperature responsive power element for powering said ejecting mechanism, the improvement of electric heating means for heating said power element comprising electric circuit means connectable to a source of electric power,

a heating element in said circuit means and situated with respect to said power element to provide heat to said power clement upon energization thereof,

switch means connected in series with said heating element for eiectively deenergizing said heating element in an open position `of said switch means, and an auxiliary heating element and a thermostat connected in series with each other and in parallel with `said switch means,

References Cited by the Examiner UNITED STATES PATENTS Nelson 62-353 X Baillif et al. 62-353 Bauerlein 62-353 Bauerlein 62-353 X ROBERT A. OLEARY, Primary Examiner. W. E. WAYNER, Assistant Examiner, 

1. IN AN ICE MAKER, MEANS FOR FORMING ICE CUBES, EJECTION MEANS ASSOCIATED WITH SAID FORMING MEANS AND OPERATIVE THROUGH SUCCESSIVE CYCLES IN GIVEN TIME PERIODS OF EJECT ICE CUBES FROM SAID FORMING MEANS SERIATIM, POWER MEANS INCLUDING A TEMPERATURE RESPONSIVE POWER ELEMENT HAVING A FORCE APPLYING MEMBER OPERATIVELY CONNECTED TO SAID EJECTION MEANS, SAID FORCE APPLYLING MEMBER BEING MOVED FROM A FIRST POSITION TO A SECOND POSITION UPON THE RAISING OF THE TEMPERATURE OF SAID POWER ELEMENT TO A HIGH TEMPERATURE AND BEING MOVED BACK AGAIN TO SAID FIRST POSITION UPON THE COOLING DOWN OF SAID POWER ELEMENT TO A LOWER TEMPERATURE TO POWER SAID EJECTION MEANS THROUGH AN OPERATING CYCLE, FIRST HEATING MEANS FUNCTIONALLY CONNECTED TO SAID POW- 